Impact of land cover change on land surface temperature over Greater Beirut Area – Lebanon

Abstract

Remote sensing (RS) technology has been used together with geographic information systems (GIS) to determine the LC types, retrieve LST, and analyze their relationships. The term Greater Beirut Area (GBA) is used to refer to the city of Beirut and its suburbs which witnessed rapid urban growth, after the end of the civil war, in the last decade of the twentieth century, due to the increase in the number of its inhabitants, and the prosperity and development of sectors such as; industrial, trade, tourism, and construction. These factors led to a wide change in the land cover (LC) types and increased land surface temperature LST. The results showed an increase in built-up areas by 29.1%, and agricultural lands by 6%, while bare land, forests, and seawater decreased by 28.5%, 4.9%, and 1.9%, respectively. These changes caused large differences in the LST between built-up areas and other LC types. The highest LST recorded was in built-up areas (33.03°C in 1985, and 34.01°C in 2020), followed by bare lands (32.61 °C in 1985 and 33.49°C in 2020), cropland (31.23°C in 1985 and 32.17°C in 2020), forest (30.08°C in 1985 and 30.47°C in 2020), and water (24.97°C in 1985 and 28.15°C in 2020). Consequently, converting different LC types into built-up areas led to increases in LST and changed microclimate.

Investigation of Thermal Heat Mapping and Vegetation Cooling Impact Using Landsat-5, -7, and -8 Imagery: A Case Study of Greater Beirut Area in Lebanon

“…GBA's topography increases in elevation from the west coastline at 0 m and extends to an elevation of 989 m. Due to demographic and economic growth pressures, many areas in GBA are transformed from green spaces, forests, and agricultural regions into residential structures, industrial areas, and other public facilities. The direct influence was to reduce the forested lands and increase surfaces with asphalt and concrete, which are utilized in urban construction and considered impermeable materials that absorb and store solar radiation [8].…”

Utilizing multi-temporal thermal data to assess environmental land degradation impacts: example from Suez Canal region, Egypt

“…The detection of the final LST map was done by the measurement of the normalized difference vegetation index (NDVI), then the conversion of TIRS band data to TOA spectral radiance, and finally, the measurement of atmospheric brightness. LST data were then converted from K to °C (Khyami 2021).…”